Microvascular Decompression for Oculomotor Nerve Palsy due to Nonaneurysmal Vascular Compression

Area of Science:

• Neuroscience
• Vascular Neurology

Background:

• Oculomotor nerve palsy (ONP) is typically associated with diabetes mellitus or aneurysmal compression.
• Nonaneurysmal vascular compression of the oculomotor nerve is an infrequently reported cause of ONP.

Observation:

• A 70-year-old nondiabetic male presented with acute left ONP.
• Magnetic resonance imaging identified the left posterior communicating artery compressing the left oculomotor nerve.

Findings:

• Surgical exploration revealed degenerative changes in the oculomotor nerve consistent with compression.
• Microvascular decompression successfully separated the posterior communicating artery from the oculomotor nerve.

Implications:

• This case supports nonaneurysmal vascular compression as a cause of ONP.
• Advanced magnetic resonance imaging is crucial for diagnosing neurovascular compression.
• Microvascular decompression is the recommended treatment for ONP due to vascular compression.